The candidate, who has a background in biochemistry and epidemiology, is currently working to combine these disciplines to do research on the biochemical epidemiology of colorectal cancer, with the long-term goal of contributing to the development of methods of primary and secondary prevention of this important disease. To help make this transition, the candidate will engage in a program of structured and independent learning in laboratory methods, cancer biology, biochemistry and microbiology of feces, and multivariate analysis. The candidate's research project is directed at identifying fecal protein markers of colorectal neoplasms, both tumor markers (biochemical indicators of the presence of a tumor) and risk markers (biochemical indicators of persons at high risk for colorectal cancer). The specific aims are: 1) to explore the potential utility of four specific fecal proteins (lysozyme, tissue polypeptide antigen, and urokinase- and tissue-type plasminogen activators) as markers by comparing the fecal levels of these proteins in persons with and without colorectal neoplasms and in persons at high and lower risk for colorectal cancer; 2) to search for other potential fecal protein markers by determining whether the electrophoretic patterns of fecal protein extracts differ between persons with and without colorectal neoplasms and between persons at high and lower risk for colorectal cancer; and 3) to establish a subject recruitment and fecal sample collection system for ongoing testing of new potential fecal markers. The candidate will contribute to the preventive oncology curriculum by working with the program director of the Comprehensive Cancer Center's Cancer Education Grant. The candidate will serve as coordinator of the new summer research program for students in combined M.D.-M.P.H. or R.N.- M.P.H. programs.